Threat modeling Halcyon's new payments feature, which handles money and personal data, around an eight-stage loop — scope, diagram, identify, assess, mitigate, validate, document and iterate. On the left, a data flow diagram excerpt with the customer, admin UI and payment gateway outside a trust boundary and the payment API, ledger service and database inside, built from 5 processes, 3 stores, 11 flows and 4 trust boundaries. In the centre the loop turns 61 threats — 47 from STRIDE and 14 privacy threats from LINDDUN — into 18 owned decisions. On the right, the register: six critical and high threats carry 82% of the risk; funds-transfer tampering is mitigated by signing and verifying transactions (SEC-412), admin privilege escalation is mitigated (SEC-418), an unused legacy endpoint is eliminated and a low-risk error leak is accepted, and validation shows the risk falling from high to low.

CY-MID-007Mid Level · Threat Modeling

Threat Modeling — The Threat Model Loop

A hands-on mid-level course that finds security problems in a design before they are built, by modeling the system and reasoning about what can go wrong. Work the threat model loop - eight stages a model cycles through: Scope, Diagram, Identify, Assess, Mitigate, Validate, Document, and Iterate - answering the four questions and ending in decisions, not a list, with real data flow diagrams, trust boundaries, STRIDE and LINDDUN enumeration, risk rating, and mitigation design. Four hands-on activities in every lesson.

15 hours8 chapters32 lessons225 activities8 labs

What you'll learn

Scope and diagram a system as data flows with trust boundaries.
Identify threats systematically with STRIDE, attacker reasoning, and LINDDUN.
Assess threats by realistic risk and decide and design mitigations in.
Validate the model, document it actionably, and keep it living in the SDLC.

Price:৳8,000